AFAIK, the US and most other countries are the same as the UK with regard to Photography in Public places - it is completely legal, as there is no copyright of faces. As long as the images are not used in a defamatory manner, for commercial purposes, or taking a photograph of certain private locations,(generally those involved with defence).
There is nothing wrong (legally), in taking a photographic image in a public place. Law enforcement cannot confiscate equipment or force someone to delete images, without a specific court order, and certainly private security personnel cannot.
It does come down to a definition of what is a public place - I was once informed that my car park, on private land, was a public place, as I used it in the course of inviting people into my business. ( at the time I was a Publican, and a customer was breathalyzed whilst getting property out of his vehicle before walking home, thus deemed as being in charge of the vehicle )
The availability of Google Glass is certainly something to be concerned about with regards to distraction of a driver
but to make the act of using them for taking a photograph, would involve a lot of re-writing of the Law